Precision thread winding machines having a spool pin, a pressure roller and reverse thread roller device are well known. Such machines are driven with spindles with the spool pin carrying a spool tube and the reverse thread roller being driven jointly with the spool pin by a motor.
In such a known thread winding apparatus, it is usual to insert the thread with a hand injector such as a suction pistol. The end of the thread is grasped by the suction pistol and simply placed into a notched groove found on the spool tube to thereby clamp the end of the thread in place on the surface of the spool tube. The thread is then cut through to separate it from the suction pistol once it has been clamped in place on the spool tube surface.
In one known configuration, the spool tube and the pin carrying the spool tube have catch slots on the front side thereof. The so-called catch slots make it possible to connect the thread with the spool tube for the purpose of carrying out the rest of the winding.
The winding-up process on the spool tube takes place in a very well known manner once a so-called reserve winding is formed. The reserve winding makes it possible to connect the start of the ready-wound spool with the end of a further spool so that the spooling of several thread rolls can be undertaken without interruption. In other words, the thread reserve winding provides a length of the thread as a lead for interconnecting separate spools being wound on the prior art winding machines.
Under special circumstances, such as at high rotational speeds of, for example, approximately 600 meters per minute or even with threads which exceed a certain thickness, disadvantages develop when winding onto the spool tube. The notched groove is more or less cracked open through the developing draw of the thread in the depth. The catch slots located at the front of spool tube are damaged or deformed so that a catching action is no longer guaranteed. The spool tubes must be exchanged because of deformation of the catch elements after a short period of time or performance.